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• Strange traffic on fresh Ubuntu Server install

  - by Fishy

  I've just installed Ubuntu Server on my home box after becoming partially familiar with it at work and wanting to train up as a Pen Tester. I installed the latest version on a logical partition (the main one contained Win7), and selected none of the extra modules (I think). I installed ngrep and fired it up (along with TCPdump) and immediately saw some strange traffic which I am unable to identify. My pc is sending out UDP packets every couple of seconds to a seemingly random series of IP addresses, all on the same port (47669 - though I did also see it use another port for a while). I watched it do this for about 20 mins, whilst trying to work out why it was doing it. The only other traffic was the odd ARP request for the router and SSDP UPnP broadcasts from the router. Anyone know what this is, or have any advice on how best to find out? Thanks. EDIT: Actually, it's not my box generating the traffic. It's receiving the traffic on that port, from a series of IP addresses, and returning 'port unreachable' messages.

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• Can't connect nonlocally after 12.10 upgrade

  - by user101815

  I've just upgraded one of my systems from 12.04 to 12.10. Now I can't connect on that system beyond my local network. Connections within the local network seem to work fine, and I can make nonlocal connections from other machines (like the one I'm asking this question from). I suspect that some routing information has been messed up, but I don't know where to look for it. It's not a nameserver problem -- pinging outside sites by their IP addresses doesn't work either. I have another laptop next to this one, also running Kubuntu 12.10. On the one that can't connect, arp produces no output. On the other one, it produces 192.168.0.1 ether 00:23:69:fa:ce:ae C wlan0 On the working machine, the output of netstat starts with some tcp entries. On the nonworking one, those entries are absent. I asked this question on the Ubuntu forum but haven't gotten any answers there. One further complication: since the troublesome machine has no outside connection, it's extremely difficult to download anything to it. For what it's worth, "ping 8.8.8.8" produces "connect: Network is unreachable". Update: after a lot of fiddling, I have my external world back. I don't know what the key action was, but the first indication of progress was that "ping 8.8.8.8" worked. At that point I still didn't have a working nameserver, so external URLs didn't work. But I did this (based on an online post, of course): sudo dpkg-reconfigure resolvconf and answered Yes to all prompts. That did the trick!! Apparently my problem was unique, or close to it, since I couldn't find any online references to it: local net working, remote net not working, including explicit IP addresses. So I suppose that if no one else has this problem, no one cares about the solution!!

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• Extended service set help [closed]

  - by Cygnus X

  Sorry, this is going to be long and rambly. So, at home my network is set up as such: I have a "master router" that handles DHCP, from there I have a basic 5 port switch, and coming off that, I have a second router that I put in access point mode so that I could have better wireless coverage in my house. I cant seem to access it through a web browser since the master router kicked in and assigned it an ip address. But, i told you all that story, so that i could tell you this story. At the company I work for, they are trying to set up wireless cameras, according to the manual for these, in order to connect these cameras to our network, we need to get into the wireless router and associate the router with the cameras, but the problem is, the network is setup like my home network. Theres a "master router" which is a windows 2003 server, and then a wireless router in AP mode dishing out wireless access. I cant get into the router (by the way I'm not the system admin for the company, nor do i know jack squat about windows server , nor can I easily get in contact with the system admin. (quite the cluster f*k, eh?)) I've tried using wireshark to find the routers ip, dug through arp tables, tried plugging straight into the router, but I cant seem to get into the damn thing. Any ideas/suggestions would be greatly appreciated.

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• ArchBeat Link-o-Rama Top 10 for October 28 - November 3, 2012

  - by Bob Rhubart

  The Top 10 most popular items shared on the OTN ArchBeat Facebook Page for the week of Oct 28 - Nov 3, 2012. Eventually, 90% of tech budgets will be outside IT departments | ZDNet Another interesting post from ZDNet blogger Joe McKendrick about changing roles in IT. ADF Mobile - Login Functionality | Andrejus Baranovskis "The new ADF Mobile approach with native deployment is cool when you want to access phone functionality (camera, email, sms and etc.), also when you want to build mobile applications with advanced UI," reports Oracle ACE Director Andrejus Baranovskis. Mobile Development Platform Strategy Chart: ADF Mobile, WebCenter Sites, Portal, Content and Social "Unlike desktop web focused efforts, the world of mobile has undergone change at a feverish pace," says social enterprise expert John Brunswick. His extensive post charts various resources that will help you keep up. ADF Essentials - The Bare Necessities | Floyd Teter The experiment is over… And now Oracle ACE Director Floyd Teter shares his impressions after spending some time with Oracle ADF Essentials, the free version of Oracle ADF. A review of Oracle SOA Suite 11g Administrator’s Handbook | RedStack "More so than any other single piece of content that I have seen on the topic, it provides the information that a SOA administrator needs to know in order to successfully configure, manage, monitor, troubleshoot and backup an Oracle SOA environment." So says Oracle Fusion Middleware A-Team solution architect Mark Nelson of Oracle SOA Suite 11g Administrator’s Handbook, by Ahmed Aboulnaga and Arun Pareek. Expanding the Oracle Enterprise Repository with functional documentation Capgemini middleware specialist Marc Kuijpers shares information on how Oracle Enterprise Repository can be configured "to contain functional assets, i.e. functional designs, use cases and a logical data model" to aid in SOA governance efforts. Podcast: Are You Future Proof? - Part 2 In Part 2, practicing architects and Oracle ACE Directors Ron Batra (AT&T), Basheer Khan (Innowave Technology), and Ronald van Luttikhuizen discuss re-tooling one’s skill set to reflect changes in enterprise IT, including the knowledge to steer stakeholders around the hype to what’s truly valuable. Easy way to access JPA with REST (JSON / XML) | Edwin Biemond Oracle ACE Edwin Biemond shows you "what is possible with JPA-RS, how easy it is and howto setup your own EclipseLink REST service." Clustering ODI11g for High-Availability Part 1: Introduction and Architecture | Richard Yeardley "JEE agents can be deployed alongside, or instead of, standalone agents," says Rittman Meade's Richard Yeardley. "But there is one key advantage in using JEE agents and WebLogic: when you deploy JEE agents as part of a WebLogic cluster they can be configured together to form a high availability cluster." Learn more in Yeardley's extensive post. 2012 IOUG Virtualization SIG – Online Symposium on Nov 7 and Nov 8 | Kai Yu Oracle ACE Director Kai Yu shares information on this week's IOUG Virtualization SIG online event. Does that make it a virtual virtualization event? Thought for the Day "If McDonalds were run like a software company, one out of every hundred Big Macs would give you food poisoning — and the response would be, 'We’re sorry, here’s a coupon for two more.'" — Mark Minasi Source: SoftwareQuotes.com

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• How to stop a ICMP attack?

  - by cumhur onat

  We are under a heavy icmp flood attack. Tcpdump shows the result below. Altough we have blocked ICMP with iptables tcpdump still prints icmp packets. I've also attached iptables configuration and "top" result. Is there any thing I can do to completely stop icmp packets? [root@server downloads]# tcpdump icmp -v -n -nn tcpdump: listening on eth0, link-type EN10MB (Ethernet), capture size 96 bytes 03:02:47.810957 IP (tos 0x0, ttl 49, id 16007, offset 0, flags [none], proto: ICMP (1), length: 56) 80.227.64.183 > 77.92.136.196: ICMP redirect 94.201.175.188 to host 80.227.64.129, length 36 IP (tos 0x0, ttl 124, id 31864, offset 0, flags [none], proto: ICMP (1), length: 76) 77.92.136.196 > 94.201.175.188: [|icmp] 03:02:47.811559 IP (tos 0x0, ttl 49, id 16010, offset 0, flags [none], proto: ICMP (1), length: 56) 80.227.64.183 > 77.92.136.196: ICMP redirect 94.201.175.188 to host 80.227.64.129, length 36 IP (tos 0x0, ttl 52, id 31864, offset 0, flags [none], proto: ICMP (1), length: 76) 77.92.136.196 > 94.201.175.188: [|icmp] 03:02:47.811922 IP (tos 0x0, ttl 49, id 16012, offset 0, flags [none], proto: ICMP (1), length: 56) 80.227.64.183 > 77.92.136.196: ICMP redirect 94.201.175.188 to host 80.227.64.129, length 36 IP (tos 0x0, ttl 122, id 31864, offset 0, flags [none], proto: ICMP (1), length: 76) 77.92.136.196 > 94.201.175.188: [|icmp] 03:02:47.812485 IP (tos 0x0, ttl 49, id 16015, offset 0, flags [none], proto: ICMP (1), length: 56) 80.227.64.183 > 77.92.136.196: ICMP redirect 94.201.175.188 to host 80.227.64.129, length 36 IP (tos 0x0, ttl 126, id 31864, offset 0, flags [none], proto: ICMP (1), length: 76) 77.92.136.196 > 94.201.175.188: [|icmp] 03:02:47.812613 IP (tos 0x0, ttl 49, id 16016, offset 0, flags [none], proto: ICMP (1), length: 56) 80.227.64.183 > 77.92.136.196: ICMP redirect 94.201.175.188 to host 80.227.64.129, length 36 IP (tos 0x0, ttl 122, id 31864, offset 0, flags [none], proto: ICMP (1), length: 76) 77.92.136.196 > 94.201.175.188: [|icmp] 03:02:47.812992 IP (tos 0x0, ttl 49, id 16018, offset 0, flags [none], proto: ICMP (1), length: 56) 80.227.64.183 > 77.92.136.196: ICMP redirect 94.201.175.188 to host 80.227.64.129, length 36 IP (tos 0x0, ttl 122, id 31864, offset 0, flags [none], proto: ICMP (1), length: 76) 77.92.136.196 > 94.201.175.188: [|icmp] 03:02:47.813582 IP (tos 0x0, ttl 49, id 16020, offset 0, flags [none], proto: ICMP (1), length: 56) 80.227.64.183 > 77.92.136.196: ICMP redirect 94.201.175.188 to host 80.227.64.129, length 36 IP (tos 0x0, ttl 52, id 31864, offset 0, flags [none], proto: ICMP (1), length: 76) 77.92.136.196 > 94.201.175.188: [|icmp] 03:02:47.814092 IP (tos 0x0, ttl 49, id 16023, offset 0, flags [none], proto: ICMP (1), length: 56) 80.227.64.183 > 77.92.136.196: ICMP redirect 94.201.175.188 to host 80.227.64.129, length 36 IP (tos 0x0, ttl 120, id 31864, offset 0, flags [none], proto: ICMP (1), length: 76) 77.92.136.196 > 94.201.175.188: [|icmp] 03:02:47.814233 IP (tos 0x0, ttl 49, id 16024, offset 0, flags [none], proto: ICMP (1), length: 56) 80.227.64.183 > 77.92.136.196: ICMP redirect 94.201.175.188 to host 80.227.64.129, length 36 IP (tos 0x0, ttl 120, id 31864, offset 0, flags [none], proto: ICMP (1), length: 76) 77.92.136.196 > 94.201.175.188: [|icmp] 03:02:47.815579 IP (tos 0x0, ttl 49, id 16025, offset 0, flags [none], proto: ICMP (1), length: 56) 80.227.64.183 > 77.92.136.196: ICMP redirect 94.201.175.188 to host 80.227.64.129, length 36 IP (tos 0x0, ttl 50, id 31864, offset 0, flags [none], proto: ICMP (1), length: 76) 77.92.136.196 > 94.201.175.188: [|icmp] 03:02:47.815726 IP (tos 0x0, ttl 49, id 16026, offset 0, flags [none], proto: ICMP (1), length: 56) 80.227.64.183 > 77.92.136.196: ICMP redirect 94.201.175.188 to host 80.227.64.129, length 36 IP (tos 0x0, ttl 50, id 31864, offset 0, flags [none], proto: ICMP (1), length: 76) 77.92.136.196 > 94.201.175.188: [|icmp] 03:02:47.815890 IP (tos 0x0, ttl 49, id 16027, offset 0, flags [none], proto: ICMP (1), length: 56) 80.227.64.183 > 77.92.136.196: ICMP redirect 94.201.175.188 to host 80.227.64.129, length 36 iptables configuration: [root@server etc]# iptables -L Chain INPUT (policy ACCEPT) target prot opt source destination ofis tcp -- anywhere anywhere tcp dpt:mysql ofis tcp -- anywhere anywhere tcp dpt:ftp DROP icmp -- anywhere anywhere Chain FORWARD (policy ACCEPT) target prot opt source destination Chain OUTPUT (policy ACCEPT) target prot opt source destination DROP icmp -- anywhere anywhere Chain ofis (2 references) target prot opt source destination ACCEPT all -- OUR_OFFICE_IP anywhere DROP all -- anywhere anywhere top: top - 03:12:19 up 400 days, 15:43, 3 users, load average: 1.49, 1.67, 2.61 Tasks: 751 total, 3 running, 748 sleeping, 0 stopped, 0 zombie Cpu(s): 8.2%us, 1.0%sy, 0.0%ni, 87.9%id, 2.1%wa, 0.1%hi, 0.7%si, 0.0%st Mem: 32949948k total, 26906844k used, 6043104k free, 4707676k buffers Swap: 10223608k total, 0k used, 10223608k free, 14255584k cached PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 36 root 39 19 0 0 0 R 100.8 0.0 17:03.56 ksoftirqd/11 10552 root 15 0 11408 1460 676 R 5.7 0.0 0:00.04 top 7475 lighttpd 15 0 304m 22m 15m S 3.8 0.1 0:05.37 php-cgi 1294 root 10 -5 0 0 0 S 1.9 0.0 380:54.73 kjournald 3574 root 15 0 631m 11m 5464 S 1.9 0.0 0:00.65 node 7766 lighttpd 16 0 302m 19m 14m S 1.9 0.1 0:05.70 php-cgi 10237 postfix 15 0 52572 2216 1692 S 1.9 0.0 0:00.02 scache 1 root 15 0 10372 680 572 S 0.0 0.0 0:07.99 init 2 root RT -5 0 0 0 S 0.0 0.0 0:16.72 migration/0 3 root 34 19 0 0 0 S 0.0 0.0 0:00.06 ksoftirqd/0 4 root RT -5 0 0 0 S 0.0 0.0 0:00.00 watchdog/0 5 root RT -5 0 0 0 S 0.0 0.0 1:10.46 migration/1 6 root 34 19 0 0 0 S 0.0 0.0 0:01.11 ksoftirqd/1 7 root RT -5 0 0 0 S 0.0 0.0 0:00.00 watchdog/1 8 root RT -5 0 0 0 S 0.0 0.0 2:36.15 migration/2 9 root 34 19 0 0 0 S 0.0 0.0 0:00.19 ksoftirqd/2 10 root RT -5 0 0 0 S 0.0 0.0 0:00.00 watchdog/2 11 root RT -5 0 0 0 S 0.0 0.0 3:48.91 migration/3 12 root 34 19 0 0 0 S 0.0 0.0 0:00.20 ksoftirqd/3 13 root RT -5 0 0 0 S 0.0 0.0 0:00.00 watchdog/3 uname -a [root@server etc]# uname -a Linux thisis.oursite.com 2.6.18-238.19.1.el5 #1 SMP Fri Jul 15 07:31:24 EDT 2011 x86_64 x86_64 x86_64 GNU/Linux arp -an [root@server downloads]# arp -an ? (77.92.136.194) at 00:25:90:04:F0:90 [ether] on eth0 ? (192.168.0.2) at 00:25:90:04:F0:91 [ether] on eth1 ? (77.92.136.193) at 00:23:9C:0B:CD:01 [ether] on eth0

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• Stop duplicate icmp echo replies when bridging to a dummy interface?

  - by mbrownnyc

  I recently configured a bridge br0 with members as eth0 (real if) and dummy0 (dummy.ko if). When I ping this machine, I receive duplicate replies as: # ping SERVERA PING SERVERA.domain.local (192.168.100.115) 56(84) bytes of data. 64 bytes from SERVERA.domain.local (192.168.100.115): icmp_seq=1 ttl=62 time=113 ms 64 bytes from SERVERA.domain.local (192.168.100.115): icmp_seq=1 ttl=62 time=114 ms (DUP!) 64 bytes from SERVERA.domain.local (192.168.100.115): icmp_seq=2 ttl=62 time=113 ms 64 bytes from SERVERA.domain.local (192.168.100.115): icmp_seq=2 ttl=62 time=113 ms (DUP!) Using tcpdump on SERVERA, I was able to see icmp echo replies being sent from eth0 and br0 itself as follows (oddly two echo request packets arrive "from" my Windows box myhost): 23:19:05.324192 IP myhost.domain.local > SERVERA.domain.local: ICMP echo request, id 512, seq 43781, length 40 23:19:05.324212 IP SERVERA.domain.local > myhost.domain.local: ICMP echo reply, id 512, seq 43781, length 40 23:19:05.324217 IP myhost.domain.local > SERVERA.domain.local: ICMP echo request, id 512, seq 43781, length 40 23:19:05.324221 IP SERVERA.domain.local > myhost.domain.local: ICMP echo reply, id 512, seq 43781, length 40 23:19:05.324264 IP SERVERA.domain.local > myhost.domain.local: ICMP echo reply, id 512, seq 43781, length 40 23:19:05.324272 IP SERVERA.domain.local > myhost.domain.local: ICMP echo reply, id 512, seq 43781, length 40 It's worth noting, testing reveals that hosts on the same physical switch do not see DUP icmp echo responses (a host on the same VLAN on another switch does see a dup icmp echo response). I've read that this could be due to the ARP table of a switch, but I can't find any info directly related to bridges, just bonds. I have a feeling my problem lay in the stack on linux, not the switch, but am opened to any suggestions. The system is running centos6/el6 kernel 2.6.32-71.29.1.el6.i686. How do I stop ICMP echo replies from being sent in duplicate when dealing with a bridge interface/bridged interfaces? Thanks, Matt [edit] Quick note: It was recommended in #linux to: [08:53] == mbrownnyc [gateway/web/freenode/] has joined ##linux [08:57] <lkeijser> mbrownnyc: what happens if you set arp_ignore to 1 for the dummy interface? [08:59] <lkeijser> also set arp_announce to 2 for that interface [09:24] <mbrownnyc> lkeijser: I set arp_annouce to 2, arp_ignore to 2 in /etc/sysctl.conf and rebooted the machine... verifying that the bits are set after boot... the problem is still present I did this and came up empty. Same dup problem. I will be moving away from including the dummy interface in the bridge as: [09:31] == mbrownnyc [gateway/web/freenode/] has joined #Netfilter [09:31] <mbrownnyc> Hello all... I'm wondering, is it correct that even with an interface in PROMISC that the kernel will drop /some/ packets before they reach applications? [09:31] <whaffle> What would you make think so? [09:32] <mbrownnyc> I ask because I am receiving ICMP echo replies after configuring a bridge with a dummy interface in order for ipt_netflow to see all packets, only as reported in it's documentation: http://ipt-netflow.git.sourceforge.net/git/gitweb.cgi?p=ipt-netflow/ipt-netflow;a=blob;f=README.promisc [09:32] <mbrownnyc> but I do not know if PROMISC will do the same job [09:33] <mbrownnyc> I was referred here from #linux. any assistance is appreciated [09:33] <whaffle> The following conditions need to be met: PROMISC is enabled (bridges and applications like tcpdump will do this automatically, otherwise they won't function). [09:34] <whaffle> If an interface is part of a bridge, then all packets that enter the bridge should already be visible in the raw table. [09:35] <mbrownnyc> thanks whaffle PROMISC must be set manually for ipt_netflow to function, but [09:36] <whaffle> promisc does not need to be set manually, because the bridge will do it for you. [09:36] <whaffle> When you do not have a bridge, you can easily create one, thereby rendering any kernel patches moot. [09:36] <mbrownnyc> whaffle: I speak without the bridge [09:36] <whaffle> It is perfectly valid to have a "half-bridge" with only a single interface in it. [09:36] <mbrownnyc> whaffle: I am unfamiliar with the raw table, does this mean that PROMISC allows the raw table to be populated with packets the same as if the interface was part of a bridge? [09:37] <whaffle> Promisc mode will cause packets with {a dst MAC address that does not equal the interface's MAC address} to be delivered from the NIC into the kernel nevertheless. [09:37] <mbrownnyc> whaffle: I suppose I mean to clearly ask: what benefit would creating a bridge have over setting an interface PROMISC? [09:38] <mbrownnyc> whaffle: from your last answer I feel that the answer to my question is "none," is this correct? [09:39] <whaffle> Furthermore, the linux kernel itself has a check for {packets with a non-local MAC address}, so that packets that will not enter a bridge will be discarded as well, even in the face of PROMISC. [09:46] <mbrownnyc> whaffle: so, this last bit of information is quite clearly why I would need and want a bridge in my situation [09:46] <mbrownnyc> okay, the ICMP echo reply duplicate issue is likely out of the realm of this channel, but I sincerely appreciate the info on the kernels inner-workings [09:52] <whaffle> mbrownnyc: either the kernel patch, or a bridge with an interface. Since the latter is quicker, yes [09:54] <mbrownnyc> thanks whaffle [edit2] After removing the bridge, and removing the dummy kernel module, I only had a single interface chilling out, lonely. I still received duplicate icmp echo replies... in fact I received a random amount: http://pastebin.com/2LNs0GM8 The same thing doesn't happen on a few other hosts on the same switch, so it has to do with the linux box itself. I'll likely end up rebuilding it next week. Then... you know... this same thing will occur again. [edit3] Guess what? I rebuilt the box, and I'm still receiving duplicate ICMP echo replies. Must be the network infrastructure, although the ARP tables do not contain multiple entries. [edit4] How ridiculous. The machine was a network probe, so I was (ingress and egress) mirroring an uplink port to a node that was the NIC. So, the flow (must have) gone like this: ICMP echo request comes in through the mirrored uplink port. (the real) ICMP echo request is received by the NIC (the mirrored) ICMP echo request is received by the NIC ICMP echo reply is sent for both. I'm ashamed of myself, but now I know. It was suggested on #networking to either isolate the mirrored traffic to an interface that does not have IP enabled, or tag the mirrored packets with dot1q.

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• Android: How to obtain Mac Address of WiFi Network Interface?

  - by Gubatron

  It seems the java.net.NetworkInterface implementation of android does not have a byte[] getHardwareAddress() method http://developer.android.com/reference/java/net/NetworkInterface.html I've found several forums of people trying to do this with no definitive answer, I need to get a somewhat cross-device UUID, so I can't rely on phone numbers or in ANDROID_ID (which can be overwritten and which I think depends on the user having a google account) http://developer.android.com/reference/android/provider/Settings.Secure.html#ANDROID_ID In linux you can use ifconfig or read from /proc/net/arp and you can easily get the Hardware address. Is there a file in android that I can read? There has to be a way to get this address since it's shown in the "Settings About Phone Status" of the phone.

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• FNhibernate, GeneratedBy.HiLo, hibernate_unique_key etc.

  - by csetzkorn

  Hi, I have started using the s#arp architecture which uses FNhibernate and GeneratedBy.HiLo to generate primary keys (there is also table hibernate_unique_key). Apparently, this is recommended practise and I would like to stick with this. Now to my problem. I have used NHibernate and hbm mapping quite a bit and usually used identity columns for my primary keys. This allowed me to seed the database using SQL. Can I do this with the aforementioned setup (hibernate_unique_key table etc.). I need to do this as SQL insert is much more efficient than using NHibernate + C# to seed the db with a million entities. Any feedback would be very much appreciated. Thanks. Christian

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• Problem of reading OWL/XML

  - by Mikae Combarado

  Hello, I have a problem reading OWL/XML files from Java using Jena. I have no problem reading RDF/XML files, but whenever I create a OWL/XML file from Protege and try to read it, Java gives this error below : WARN [main] (RDFDefaultErrorHandler.java:36) Exception in thread "main" java.lang.NullPointerException at com.hp.hpl.jena.rdf.arp.impl.XMLHandler.endElement(XMLHandler.java:143) The code that I use to retrieve RDF/XML is below : OntModel ontModel = ModelFactory.createOntologyModel(); InputStream in = FileManager.get().open(inputFileName); if (in == null) { throw new IllegalArgumentException( "File: " + inputFileName + " not found"); } ontModel.read(in, ""); This code works with RDF/XML perfectly. However, I cannot read an OWL/XML. I looked at Internet and I couldn't find anything. I would really appreciate, if someone shows me a way. Many thanks

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• Need help using the Windows IP Helper API & ParseNetworString in C#.

  - by JohnnyNoir

  I'm attempting to rewrite some C# web service code that uses the Windows IP Helper API call "SendARP" to retreive a remote system's MAC address. SendARP works great - until you cross a network segment as Arp requests aren't routed. I've been looking at the "ParseNetworkString" documentation after happening across its existance on StackOverflow. The quick & dirty algorithm I have in mind is: public static string GetMacAddress(string strHostOrIP) { if (strHostOrIP is IPAddress) { parse results of nbstat -A strHostOrIP return macAddress } if (strHostOrIP is Hostname) { IPHostEntry hostEntry = null; try { hostEntry = Dns.GetHostEntry(strHostOrIP); } catch { return null; } if (hostEntry.AddressList.Length == 0) { return null; } foreach (IPAddress ip in hostEntry.AddressList) { if (ip.AddressFamily == System.Net.Sockets.AddressFamily.InterNetwork) { ipAddress = ip; break; } } } return GetMACAddress(ipAddress); } "ParseNetworkString" is new with Vista/Win2008 so I haven't been able to find example C# code demonstrating its use and I'm no C++ coder so if anyone can point me in the right direction...

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• ASP.NET MVC v1 project upgraded to VS 2010 no longer will debug. Why?

  - by Todd Brooks

  I'm getting the message "The breakpoint will not currently be hit. No symbols have been loaded for this document." I have a S#arp Architecture project (ASP.NET MVC v1) that has been opened and upgraded to be used in VS 2010. I can no longer debug the project. I'm running Windows 7 Ultimate x64 and Visual Studio 2010 Ultimate. I have IE set to be my default browser. I have the build set to debug. System.Web.Mvc is referenced in my project's lib dir. I've cleaned the solution. I've recompiled the solution. It's set to use .NET Framework 3.5. PDBs are being created and dropped into the bin directory with the DLLs. Any help will be greatly appreciated.

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• Are there any web application frameworks usable with .NET 2.0?

  - by adhocgeek

  Apologies if this has been asked many, many times before - I'm afraid I couldn't find any satisfactory answers. I'm stuck in an environment (a bank) where, although we have VS 2008 on the development machines, production machines are locked down to the .Net framework 2.0 and SQL Server 2005. Are there any modern application frameworks that I could employ? I've looked at things like Spring.NET, PureMVC and ASP.NET MVC (S#arp Arch?), but I don't really have the luxury of time to investigate in depth. I don't want to initiate a war over which framework might be best, I just want to know if there are any I can actually use.

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• Why Software Sucks...and What You Can Do About It – book review

  - by DigiMortal

      How do our users see the products we are writing for them and how happy they are with our work? Are they able to get their work done without fighting with cool features and crashes or are they just switching off resistance part of their brain to survive our software? Yeah, the overall picture of software usability landscape is not very nice. Okay, it is not even nice. But, fortunately, Why Software Sucks...and What You Can Do About It by David S. Platt explains everything. Why Software Sucks… is book for software users but I consider it as a-must reading also for developers and specially for their managers whose politics often kills all usability topics as soon as they may appear. For managers usability is soft topic that can be manipulated the way it is best in current state of project. Although developers are not UI designers and usability experts they are still very often forced to deal with these topics and this is how usability problems start (of course, also designers are able to produce designs that are stupid and too hard to use for users, but this blog here is about development). I found this book to be very interesting and funny reading. It is not humor book but it explains you all so you remember later very well what you just read. It took me about three evenings to go through this book and I am still enjoying what I found and how author explains our weird young working field to end users. I suggest this book to all developers – while you are demanding your management to hire or outsource usability expert you are at least causing less pain to end users. So, go and buy this book, just like I did. And… they thanks to mr. Platt :) There is one book more I suggest you to read if you are interested in usability - Don't Make Me Think: A Common Sense Approach to Web Usability, 2nd Edition by Steve Krug. Editorial review from Amazon Today’s software sucks. There’s no other good way to say it. It’s unsafe, allowing criminal programs to creep through the Internet wires into our very bedrooms. It’s unreliable, crashing when we need it most, wiping out hours or days of work with no way to get it back. And it’s hard to use, requiring large amounts of head-banging to figure out the simplest operations. It’s no secret that software sucks. You know that from personal experience, whether you use computers for work or personal tasks. In this book, programming insider David Platt explains why that’s the case and, more importantly, why it doesn’t have to be that way. And he explains it in plain, jargon-free English that’s a joy to read, using real-world examples with which you’re already familiar. In the end, he suggests what you, as a typical user, without a technical background, can do about this sad state of our software—how you, as an informed consumer, don’t have to take the abuse that bad software dishes out. As you might expect from the book’s title, Dave’s expose is laced with humor—sometimes outrageous, but always dead on. You’ll laugh out loud as you recall incidents with your own software that made you cry. You’ll slap your thigh with the same hand that so often pounded your computer desk and wished it was a bad programmer’s face. But Dave hasn’t written this book just for laughs. He’s written it to give long-overdue voice to your own discovery—that software does, indeed, suck, but it shouldn’t. Table of contents Acknowledgments xiii Introduction Chapter 1: Who’re You Calling a Dummy? Where We Came From Why It Still Sucks Today Control versus Ease of Use I Don’t Care How Your Program Works A Bad Feature and a Good One Stopping the Proceedings with Idiocy Testing on Live Animals Where We Are and What You Can Do Chapter 2: Tangled in the Web Where We Came From How It Works Why It Still Sucks Today Client-Centered Design versus Server-Centered Design Where’s My Eye Opener? It’s Obvious—Not! Splash, Flash, and Animation Testing on Live Animals What You Can Do about It Chapter 3: Keep Me Safe The Way It Was Why It Sucks Today What Programmers Need to Know, but Don’t A Human Operation Budgeting for Hassles Users Are Lazy Social Engineering Last Word on Security What You Can Do Chapter 4: Who the Heck Are You? Where We Came From Why It Still Sucks Today Incompatible Requirements OK, So Now What? Chapter 5: Who’re You Looking At? Yes, They Know You Why It Sucks More Than Ever Today Users Don’t Know Where the Risks Are What They Know First Milk You with Cookies? Privacy Policy Nonsense Covering Your Tracks The Google Conundrum Solution Chapter 6: Ten Thousand Geeks, Crazed on Jolt Cola See Them in Their Native Habitat All These Geeks Who Speaks, and When, and about What Selling It The Next Generation of Geeks—Passing It On Chapter 7: Who Are These Crazy Bastards Anyway? Homo Logicus Testosterone Poisoning Control and Contentment Making Models Geeks and Jocks Jargon Brains and Constraints Seven Habits of Geeks Chapter 8: Microsoft: Can’t Live With ’Em and Can’t Live Without ’Em They Run the World Me and Them Where We Came From Why It Sucks Today Damned if You Do, Damned if You Don’t We Love to Hate Them Plus ça Change Growing-Up Pains What You Can Do about It The Last Word Chapter 9: Doing Something About It 1. Buy 2. Tell 3. Ridicule 4. Trust 5. Organize Epilogue About the Author

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• The Internet Key Wave MW833UP is not recognized in Ubuntu

  - by gio900

  I can't use my Onda MW833UP... :( Any advice? Here is something that someone else may understand: ~$: lsb_release -a No LSB modules are available. Distributor ID: Ubuntu Description: Ubuntu 11.10 Release: 11.10 Codename: oneiric ~$: lsusb Bus 001 Device 005: ID 1ee8:0012 ~$: dmesg [ 22.709475] cdc_acm 1-1:1.0: ttyACM0: USB ACM device [ 22.714856] usbcore: registered new interface driver cdc_acm [ 22.714866] cdc_acm: USB Abstract Control Model driver for USB modems and ISDN adapters [ 23.520490] ieee80211 phy0: wl_ops_bss_info_changed: arp filtering: enabled true, count 1 (implement) [ 24.244530] usbcore: registered new interface driver usbserial [ 24.244575] USB Serial support registered for generic [ 24.244673] usbcore: registered new interface driver usbserial_generic [ 24.244681] usbserial: USB Serial Driver core [ 24.265879] USB Serial support registered for GSM modem (1-port) [ 24.285680] usbcore: registered new interface driver option [ 24.285691] option: v0.7.2:USB Driver for GSM modems [ 24.425878] EXT4-fs (sda9): re-mounted. Opts: errors=remount-ro,commit=600 [ 24.736540] EXT4-fs (sda8): re-mounted. Opts: commit=600 [ 35.705796] Easy slow down manager: checking for SABI support. [ 35.706002] Easy slow down manager: SABI is supported (f5189) [ 36.060099] usbcore: deregistering interface driver uvcvideo [ 139.508061] CE: hpet increased min_delta_ns to 20113 nsec [ 6798.378917] usb 1-1: USB disconnect, device number 5 [ 6809.108232] usb 1-1: new high speed USB device number 6 using ehci_hcd [ 6809.242692] scsi5 : usb-storage 1-1:1.0 [ 6810.241257] scsi 5:0:0:0: CD-ROM Onda Datacard CD-ROM 0001 PQ: 0 ANSI: 0 [ 6810.241841] scsi 5:0:0:1: Direct-Access Onda Storage 0001 PQ: 0 ANSI: 0 [ 6810.271410] sr0: scsi3-mmc drive: 0x/0x caddy [ 6810.272099] sr 5:0:0:0: Attached scsi CD-ROM sr0 [ 6810.272852] sr 5:0:0:0: Attached scsi generic sg1 type 5 [ 6810.279954] sd 5:0:0:1: [sdb] Attached SCSI removable disk [ 6810.281210] sd 5:0:0:1: Attached scsi generic sg2 type 0 [ 6810.380591] sr0: CDROM (ioctl) error, command: Xpwrite, Read disk info 51 00 00 00 00 00 00 00 02 00 [ 6810.380617] sr: Sense Key : Hardware Error [current] [ 6810.380625] sr: Add. Sense: No additional sense information [ 6810.613937] sr0: CDROM (ioctl) error, command: Xpwrite, Read disk info 51 00 00 00 00 00 00 00 02 00 [ 6810.613972] sr: Sense Key : Hardware Error [current] [ 6810.613984] sr: Add. Sense: No additional sense information [ 6810.673716] usb 1-1: USB disconnect, device number 6 [ 6815.572142] usb 1-1: new high speed USB device number 7 using ehci_hcd [ 6815.706828] cdc_acm 1-1:1.0: ttyACM0: USB ACM device The last 3 lines are where I inserted the Internet key, then reconnected it. usb-device T: Bus=01 Lev=01 Prnt=01 Port=00 Cnt=01 Dev#= 7 Spd=480 MxCh= 0 D: Ver= 2.00 Cls=ef(misc ) Sub=02 Prot=01 MxPS=64 #Cfgs= 1 P: Vendor=1ee8 ProdID=0012 Rev=00.01 S: Manufacturer=Onda S: Product=MW833UP S: SerialNumber=9230B35D870F9CB7AE684EACC5C12BE5EC33B26E C: #Ifs= 2 Cfg#= 1 Atr=a0 MxPwr=500mA I: If#= 0 Alt= 0 #EPs= 1 Cls=02(commc) Sub=02 Prot=01 Driver=cdc_acm I: If#= 1 Alt= 0 #EPs= 2 Cls=0a(data ) Sub=00 Prot=00 Driver=cdc_acm Then there is /dev/ttyACM0. When the key is connected to the USB port, everything that will meant...

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• Wifi problems after upgrading to 13.10

  - by Simon

  I just upgraded to Ubuntu 13.10, but since the upgrade I don't have internet access via wifi anymore. I can: See networks Connect to a network Ping myself (localhost, 192.168.0.103) I can't: Ping others (including other devices on the same wireless network, including the gateway/router) Resolve hosts Access any other external resource, whether on my own network or on the internet Using Wireshark, I noticed my computer is continuously sending ARP-requests like "Who has 192.168.0.1 [which is the gateway]? Tell 192.168.0.103". It doesn't get any replies though. When I ping another IP-address for which it knows the mac-address (from cache), it turns out a packet loss of 90% occurs, and even if a packet manages to arrive it takes around 3000ms. The output of route -n is: Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 0.0.0.0 192.168.0.1 0.0.0.0 UG 0 0 0 eth1 192.168.0.0 0.0.0.0 255.255.255.0 U 9 0 0 eth1 192.168.122.0 0.0.0.0 255.255.255.0 U 0 0 0 virbr0 Before upgrading, wifi worked fine. Using other devices, wifi still works fine.Resetting the router didn't help. Ethernet still works after upgrading. Any suggestions? Update: I'm using the wl driver. Here's the relevant output of some commands: lspci | grep Wireless 03:00.0 Network controller: Broadcom Corporation BCM4313 802.11bgn Wireless Network Adapter (rev 01) cat /etc/modprobe.d/blacklist.conf [...] blacklist mac80211 blacklist brcm80211 blacklist cfg80211 blacklist lib80211_crypt_tkip blacklist lib80211 blacklist b43 cat /etc/rc.local sudo modprobe -r lib80211 sudo insmod /lib/modules/3.2.0-30-generic-pae/kernel/net/wireless/lib80211.ko sudo insmod /lib/modules/3.2.0-30-generic-pae/kernel/net/wireless/lib80211_crypt_wep.ko sudo insmod /lib/modules/3.2.0-30-generic-pae/kernel/net/wireless/lib80211_crypt_tkip.ko sudo insmod /lib/modules/3.2.0-30-generic-pae/kernel/net/wireless/lib80211_crypt_ccmp.ko sudo modprobe wl exit 0 The last lines are probably how I got wireless working after the previous upgrade (wireless has been a problem after each upgrade). Update 2: added information about the exact hardware below. The hardware is an integrated device, so I ran lspci -nn | grep -i network. The output is: 03:00.0 Network controller [0280]: Broadcom Corporation BCM4313 802.11bgn Wireless Network Adapter [14e4:4727] (rev 01)

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• RouterOS on Hyper-V (v3/2012) - any way to get it working?

  - by TomTom

  Trying to set up a small VPN point to connect into a remote Hyper-V cluster using ROuterOS. Anyone got it working ON Hyper-V with the latest builds of RouterOS? It seems the legacy network adapter is not supported anymore either (or just broken). The platform is a Windows Server 2012 RC. This is not a high performance setup - the RouterOS wont do the routing for more than the backend administrative access, and the only real traffic we will see there is when ISO images for new operating systems are uploaded. Otherwise we will have possibly RDP traffic as well as web / http traffioc, but this is internal only (dashboards, some control panel). The server has no public business. So the price for non virtualized network cards is ok for me. After hooking up - ping just does not work. After some time I see in windows (arp -a on the command line), so I know that the Hyper-V side is set up properly. Just no packets arrived. I have turned off all protection on Hyper-V (or : not turned them on), so no MAC spoofing protection etc. in the Advanced page for the legacy adapters. Unless I can get it work I will have to resort to using a windows install as router / VPN endpoint, which introduces another OS into the fabric (we run all routers etc. so far on mikrotik in hardware, which is why I want this one to be RouterOS, too). And no, putting hardware there is NOT an option - the cost would be significant.

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• Error 720 on VPN (PPTP) attempt

  - by Andy Shulman

  When I attempt to connect to a server running XP x64 (so essentially Server 2003) using a PPTP connection, it fails with client-side error Registering your computer on the network... Error 720: A connection to the remote computer could not be established. You might need to change the network settings for this configuration. and server-side error Event ID: 20050 The user WINSERV3\Andy connected to port VPN8-1 has been disconnected because no network protocols were successfully negotiated. I have configured the router to pass both TCP packets on 1723 and GRE packets. I have used Wireshark (filtering out ARP, UDP, and all TCP ports other than 1723) to observe the packets received by the server. Wireshark does not explicitly name any protocol GRE, but it does tell me the server sent and received TCP, PPTP, PPP LCP, PPP CHAP, PPP CBCP, and PPP IPCP. The connection seems to go wrong at packet 30, where the protocol is PPP LCP, with the payload of the packet being labeled "Protocol Reject". Obviously, this is going from server to client. This would seem to lead to the conclusion that there is something wrong with my client, which runs Windows 7 Ultimate x64. However, it is able to connect to my house's router, which runs the DD-WRT firmware and is thus a PPTP endpoint. I'm thoroughly at a loss. Please help!

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• Enable RemoteApp Full Desktop programmatically

  - by Scott Chamberlain

  I am writing a powershell script to set up some HyperV VM's however there is one step I am having trouble automating. How do I check the box to allow Remote desktop access from the RemoteApp settings programmatically? I can set up all of my customizations I need by doing #build the secrity descriptor so the desktop only shows up for people who should be allowed to see it $remoteDesktopUsersSid = New-Object System.Security.Principal.SecurityIdentifier($remoteDesktopUsersGroup.objectSid[0],0) $aceTemplet = 'O:WDG:WDD:ARP(A;CIOI;CCLCSWLORCGR;;;{0})' $securityDescriptor = $aceTemplet -f $remoteDesktopUsersSid #get a copy of the WMI instance $tsRemoteDesktop = Get-WmiObject -Namespace root\CIMV2\TerminalServices -Class Win32_TSRemoteDesktop #set settings $tsRemoteDesktop.Name = $ServerDisplayName $tsRemoteDesktop.SecurityDescriptor = $securityDescriptor $tsRemoteDesktop.IconPath = $IconPath $tsRemoteDesktop.IconIndex = $IconIndex #push settings back to server Set-WmiInstance -InputObject $tsRemoteDesktop -PutType UpdateOnly however the instance of that WMI object does not exist until after you have the above box checked. I attempted to use Set-WmiInstance to instantiate and set the settings at the same time but I keep getting errors like: Set-WmiInstance : At line:53 char:16 + Set-WmiInstance <<<< -Namespace root\CIMV2\TerminalServices -Class Win32_TSRemoteDesktop -Arguments @{Alias='TSRemoteDesktop';Name=$ServerDisplayName;ShowInPortal=$true;SecurityDescriptor=$securityDescriptor} + CategoryInfo : NotSpecified: (:) [Set-WmiInstance], ArgumentException + FullyQualifiedErrorId : System.ArgumentException,Microsoft.PowerShell.Commands.SetWmiInstance (also after running the command and getting the error it will delete the instance of Win32_TSRemoteDesktop if it already exited and un-check the box in the properties setting) Is there any way to programmatically check that box or can anyone help with why Set-WmiInstance throws that error?

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• Vmware Player 3.0 - cannot ping 32 bits guest from 64 bits (guest or host)

  - by npmj

  I'm stuck with what seems a bug in VmWare Player (build 203739). I'm using W7 Ultimate 64bits as host and have a CentOS 5.4 (64 bits) as a guest and a Windows XP Professional SP3 (32 bits) as another guest. From the 64 bits machines (the host and the linux guest) I cannot ping the windows XP. Off course, I already turned off the windows firewall in the guest and also in the host. The network is pretty basic, I'm using Vmnet8 (NAT), with DHCP and port forwarding (to the windows XP's IP). Everything is working ok, I have internet access from host and from both guests. Port forwarding to the XP guest is working ok too. The only problem is that I cannot access the XP guest through the Vmnet8. I monitored the traffic using wireshark (in the host and in the windows guest). If I try to ping the XP guest from the host, what I see is the ARP request leaving the host, being answered by the guest and, after that, there is no echo request leaving the host. The same occurs if I try to ping the XP from the CentOs guest. From the windows XP guest I can ping both the host and the CentOs guest. From the XP guest I can access the host shares. Obviously, from the host I cannot see the XP shares (as I cannot even ping the guest). I want to maintain this setup (using NAT to share the host's internet connection). Any suggestions?

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• Vmware Player 3.0 - cannot ping 32 bits guest from 64 bits (guest or host)

  - by npmj

  I'm stuck with what seems a bug in VmWare Player (build 203739). I'm using W7 Ultimate 64bits as host and have a CentOS 5.4 (64 bits) as a guest and a Windows XP Professional SP3 (32 bits) as another guest. From the 64 bits machines (the host and the linux guest) I cannot ping the windows XP. Off course, I already turned off the windows firewall in the guest and also in the host. The network is pretty basic, I'm using Vmnet8 (NAT), with DHCP and port forwarding (to the windows XP's IP). Everything is working ok, I have internet access from host and from both guests. Port forwarding to the XP guest is working ok too. The only problem is that I cannot access the XP guest through the Vmnet8. I monitored the traffic using wireshark (in the host and in the windows guest). If I try to ping the XP guest from the host, what I see is the ARP request leaving the host, being answered by the guest and, after that, there is no echo request leaving the host. The same occurs if I try to ping the XP from the CentOs guest. From the windows XP guest I can ping both the host and the CentOs guest. From the XP guest I can access the host shares. Obviously, from the host I cannot see the XP shares (as I cannot even ping the guest). I want to maintain this setup (using NAT to share the host's internet connection). Any suggestions?

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• Slow upload speeds with pfsense virtual appliance

  - by Justin Shin

  I have a pfSense virtual appliance set up in front of a Windows server. The pfSense appliance has been configured with two L2L IPSec VPN sites and not too much else. The appliance has two vNics which both exist on the same VLAN, but one is "WAN" and the other is "LAN." When I run speedtest.net on my Windows server when I have configured it to use a static WAN address and gateway, I get great speeds - maybe around 50 down, 15 up. However, when I configure it with a private IP address, I get similar download speeds but terrible upload speeds - around 2 or 3 Mbps consistently. I used Wireshark to see what gives but there didn't appear to be too much helpful information there, or I just could not find it. Besides the L2L VPNs, other configurations include: Automatic Outbound NAT Virtual P-ARP IP for the Windows Server WAN Firewall rule to allow * to * on RDP WAN Firewall rule to allow * to * (enabled this just for testing... didn't help!) No DHCP or any other services besides IPSec VPN No Errors LAN or WAN No collisions LAN or WAN I would be happy to post the full config file if it would help. I've been scratching my head at this one all day!

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• Is one server on a vlan unnecessary?

  - by moomoochoo

  DETAILS I've been researching web hosting solutions in Japan. Based on this question one of the services available seems to be a VLAN. I've read about the advantages of such a system for a large organization, but there doesn't seem to be much information regarding smaller setups. I take that to mean that for one server it is likely to be unnecessary? My concern is that I don't know how many other servers are on the WAN, so regardless of how many servers I use a VLAN might still be a good idea. SERVER INFO One dedicated server would be used. It would not be virtualized. My Research so far Based on comments here, a VLAN would be useful for mitigating these problems. A user on another server could, either mistakenly or maliciously, assign one of your IP addresses to their server, resulting in a "duplicate IP" situation that would cause connectivity issues. A user on another server could poison the arp cache and potentially redirect traffic to snoop on communication intended to/from your server. (later in the discussion this point was said to be unrealistic.) QUESTION Is it worthwhile getting a vlan for one dedicated server? Will it be easier/the same/ harder to manage?

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• Virtual bridged networking with VLAN, could not ping

  - by v.yegy

  I require a virtual network with VLAN be build between two virtual hosts - which can be (lxc/ vbox -ubuntu or win xp). I tried with lxc and vbox with Ubuntu and was finding difficult to make it work without vlan, but was successful with vbox with xp. vbox-xp1 --- br1 ---------------- br2 ---- vbox-xp2 The config is: brctl addbr br1; brctl addbr br2 ifconfig br1 up; ifconfig br2 up stp br1 off; stp br2 off ip link add name br1-br2-l0 type veth peer name br1-br2-l1 sudo brctl addif br1 br1-br2-l0 sudo brctl addif br2 br1-br2-l1 vbox - xp 1 and 2 with network ; bridged and br1 and br2 respectively. The adapter is intel PRO/1000 MT Server and driver installed in guests. Configured IPs and two hosts pinged! VLAN config: ip link add link br1 name br1-2.5 type vlan id 5 brctl addif br2 br1-2.5 create vlan 5 in xp 1 and 2 and assign ip address Ping on with this config does not work. Wireshark trace on interface br1-br2-l1 / br1-2.5 shows that one ping results in ~240 ping packets and each growing by 4 bytes - first one being correct and 60, ping does not reach other host as I see mac is not learnt[arp -a]. -- if br1-2.5 is not configured, I see untagged packets in br1-br2-l1/0, but still not reaching other host as mac is not learnt. if br1-br2-l0/1 is made down, even if br1-2.5 is up, I count not see any packets. I tried with ebtables, but still could not make a correct config to work. -- If any one here are aware of any configuration, please let me know. I need to make a network of switches. Seems I have a very long way. Sorry for a very long question. Thanks and regards, vy

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• Inbound SIP calls through Cisco 881 NAT hang up after a few seconds

  - by MasterRoot24

  I've recently moved to a Cisco 881 router for my WAN link. I was previously using a Cisco Linksys WAG320N as my modem/router/WiFi AP/NAT firewall. The WAG320N is now running in bridged mode, so it's simply acting as a modem with one of it's LAN ports connected to FE4 WAN on my Cisco 881. The Cisco 881 get's a DHCP provided IP from my ISP. My LAN is part of default Vlan 1 (192.168.1.0/24). General internet connectivity is working great, I've managed to setup static NAT rules for my HTTP/HTTPS/SMTP/etc. services which are running on my LAN. I don't know whether it's worth mentioning that I've opted to use NVI NAT (ip nat enable as opposed to the traditional ip nat outside/ip nat inside) setup. My reason for this is that NVI allows NAT loopback from my LAN to the WAN IP and back in to the necessary server on the LAN. I run an Asterisk 1.8 PBX on my LAN, which connects to a SIP provider on the internet. Both inbound and outbound calls through the old setup (WAG320N providing routing/NAT) worked fine. However, since moving to the Cisco 881, inbound calls drop after around 10 seconds, whereas outbound calls work fine. The following message is logged on my Asterisk PBX: [Dec 9 15:27:45] WARNING[27734]: chan_sip.c:3641 retrans_pkt: Retransmission timeout reached on transmission [email protected] for seqno 1 (Critical Response) -- See https://wiki.asterisk.org/wiki/display/AST/SIP+Retransmissions Packet timed out after 6528ms with no response [Dec 9 15:27:45] WARNING[27734]: chan_sip.c:3670 retrans_pkt: Hanging up call [email protected] - no reply to our critical packet (see https://wiki.asterisk.org/wiki/display/AST/SIP+Retransmissions). (I know that this is quite a common issue - I've spend the best part of 2 days solid on this, trawling Google.) I've done as I am told and checked https://wiki.asterisk.org/wiki/display/AST/SIP+Retransmissions. Referring to the section "Other SIP requests" in the page linked above, I believe that the hangup to be caused by the ACK from my SIP provider not being passed back through NAT to Asterisk on my PBX. I tried to ascertain this by dumping the packets on my WAN interface on the 881. I managed to obtain a PCAP dump of packets in/out of my WAN interface. Here's an example of an ACK being reveived by the router from my provider: 689 21.219999 193.x.x.x 188.x.x.x SIP 502 Request: ACK sip:[email protected] | However a SIP trace on the Asterisk server show's that there are no ACK's received in response to the 200 OK from my PBX: http://pastebin.com/wwHpLPPz In the past, I have been strongly advised to disable any sort of SIP ALGs on routers and/or firewalls and the many posts regarding this issue on the internet seem to support this. However, I believe on Cisco IOS, the config command to disable SIP ALG is no ip nat service sip udp port 5060 however, this doesn't appear to help the situation. To confirm that config setting is set: Router1#show running-config | include sip no ip nat service sip udp port 5060 Another interesting twist: for a short period of time, I tried another provider. Luckily, my trial account with them is still available, so I reverted my Asterisk config back to the revision before I integrated with my current provider. I then dialled in to the DDI associated with the trial trunk and the call didn't get hung up and I didn't get the error above! To me, this points at the provider, however I know, like all providers do, will say "There's no issues with our SIP proxies - it's your firewall." I'm tempted to agree with this, as this issue was not apparent with the old WAG320N router when it was doing the NAT'ing. I'm sure you'll want to see my running-config too: ! ! Last configuration change at 15:55:07 UTC Sun Dec 9 2012 by xxx version 15.2 no service pad service tcp-keepalives-in service tcp-keepalives-out service timestamps debug datetime msec localtime show-timezone service timestamps log datetime msec localtime show-timezone no service password-encryption service sequence-numbers ! hostname Router1 ! boot-start-marker boot-end-marker ! ! security authentication failure rate 10 log security passwords min-length 6 logging buffered 4096 logging console critical enable secret 4 xxx ! aaa new-model ! ! aaa authentication login local_auth local ! ! ! ! ! aaa session-id common ! memory-size iomem 10 ! crypto pki trustpoint TP-self-signed-xxx enrollment selfsigned subject-name cn=IOS-Self-Signed-Certificate-xxx revocation-check none rsakeypair TP-self-signed-xxx ! ! crypto pki certificate chain TP-self-signed-xxx certificate self-signed 01 quit no ip source-route no ip gratuitous-arps ip auth-proxy max-login-attempts 5 ip admission max-login-attempts 5 ! ! ! ! ! no ip bootp server ip domain name dmz.merlin.local ip domain list dmz.merlin.local ip domain list merlin.local ip name-server x.x.x.x ip inspect audit-trail ip inspect udp idle-time 1800 ip inspect dns-timeout 7 ip inspect tcp idle-time 14400 ip inspect name autosec_inspect ftp timeout 3600 ip inspect name autosec_inspect http timeout 3600 ip inspect name autosec_inspect rcmd timeout 3600 ip inspect name autosec_inspect realaudio timeout 3600 ip inspect name autosec_inspect smtp timeout 3600 ip inspect name autosec_inspect tftp timeout 30 ip inspect name autosec_inspect udp timeout 15 ip inspect name autosec_inspect tcp timeout 3600 ip cef login block-for 3 attempts 3 within 3 no ipv6 cef ! ! multilink bundle-name authenticated license udi pid CISCO881-SEC-K9 sn ! ! username xxx privilege 15 secret 4 xxx username xxx secret 4 xxx ! ! ! ! ! ip ssh time-out 60 ! ! ! ! ! ! ! ! ! interface FastEthernet0 no ip address ! interface FastEthernet1 no ip address ! interface FastEthernet2 no ip address ! interface FastEthernet3 switchport access vlan 2 no ip address ! interface FastEthernet4 ip address dhcp no ip redirects no ip unreachables no ip proxy-arp ip nat enable duplex auto speed auto ! interface Vlan1 ip address 192.168.1.1 255.255.255.0 no ip redirects no ip unreachables no ip proxy-arp ip nat enable ! interface Vlan2 ip address 192.168.0.2 255.255.255.0 ! ip forward-protocol nd ip http server ip http access-class 1 ip http authentication local ip http secure-server ip http timeout-policy idle 60 life 86400 requests 10000 ! ! no ip nat service sip udp port 5060 ip nat source list 1 interface FastEthernet4 overload ip nat source static tcp x.x.x.x 80 interface FastEthernet4 80 ip nat source static tcp x.x.x.x 443 interface FastEthernet4 443 ip nat source static tcp x.x.x.x 25 interface FastEthernet4 25 ip nat source static tcp x.x.x.x 587 interface FastEthernet4 587 ip nat source static tcp x.x.x.x 143 interface FastEthernet4 143 ip nat source static tcp x.x.x.x 993 interface FastEthernet4 993 ip nat source static tcp x.x.x.x 1723 interface FastEthernet4 1723 ! ! logging trap debugging logging facility local2 access-list 1 permit 192.168.1.0 0.0.0.255 access-list 1 permit 192.168.0.0 0.0.0.255 no cdp run ! ! ! ! control-plane ! ! banner motd Authorized Access only ! line con 0 login authentication local_auth length 0 transport output all line aux 0 exec-timeout 15 0 login authentication local_auth transport output all line vty 0 1 access-class 1 in logging synchronous login authentication local_auth length 0 transport preferred none transport input telnet transport output all line vty 2 4 access-class 1 in login authentication local_auth length 0 transport input ssh transport output all ! ! end ...and, if it's of any use, here's my Asterisk SIP config: [general] context=default ; Default context for calls allowoverlap=no ; Disable overlap dialing support. (Default is yes) udpbindaddr=0.0.0.0 ; IP address to bind UDP listen socket to (0.0.0.0 binds to all) ; Optionally add a port number, 192.168.1.1:5062 (default is port 5060) tcpenable=no ; Enable server for incoming TCP connections (default is no) tcpbindaddr=0.0.0.0 ; IP address for TCP server to bind to (0.0.0.0 binds to all interfaces) ; Optionally add a port number, 192.168.1.1:5062 (default is port 5060) srvlookup=yes ; Enable DNS SRV lookups on outbound calls ; Note: Asterisk only uses the first host ; in SRV records ; Disabling DNS SRV lookups disables the ; ability to place SIP calls based on domain ; names to some other SIP users on the Internet ; Specifying a port in a SIP peer definition or ; when dialing outbound calls will supress SRV ; lookups for that peer or call. directmedia=no ; Don't allow direct RTP media between extensions (doesn't work through NAT) externhost=<MY DYNDNS HOSTNAME> ; Our external hostname to resolve to IP and be used in NAT'ed packets localnet=192.168.1.0/24 ; Define our local network so we know which packets need NAT'ing qualify=yes ; Qualify peers by default dtmfmode=rfc2833 ; Set the default DTMF mode disallow=all ; Disallow all codecs by default allow=ulaw ; Allow G.711 u-law allow=alaw ; Allow G.711 a-law ; ---------------------- ; SIP Trunk Registration ; ---------------------- ; Orbtalk register => <MY SIP PROVIDER USER NAME>:[email protected]/<MY DDI> ; Main Orbtalk number ; ---------- ; Trunks ; ---------- [orbtalk] ; Main Orbtalk trunk type=peer insecure=invite host=sipgw3.orbtalk.co.uk nat=yes username=<MY SIP PROVIDER USER NAME> defaultuser=<MY SIP PROVIDER USER NAME> fromuser=<MY SIP PROVIDER USER NAME> secret=xxx context=inbound I really don't know where to go with this. If anyone can help me find out why these calls are being dropped off, I'd be grateful if you could chime in! Please let me know if any further info is required.

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• ProCurve network expansion

  - by Blue Warrior NFB

  I've hit a bit of a wall with our network scale-out. As it stands right now: We have five ProCurve 2910al switches connected as above, but with 10GbE connections (two CX4, two fiber). This fully populates the central switch above, there will be no more 10GbE Ethernet connections from that device. This group of switches is not stacked (no stack directive). Sometime in the next two or three months I'll need to add a sixth, and I'm not sure how deep of a hole I'm in. Ideally I'd replace the core switch with something more capable and has more 10GbE ports. However, that's a major outage and that requires special scheduling. The two edge switches connected via fiber have dual-port 10GbE cards in them, so I could physically put another switch on the far end of one of those. I don't know how much of a good or bad idea that would be though. Is that too many segments between end-points? Some config-excerpts: Running configuration: ; J9147A Configuration Editor; Created on release #W.14.49 hostname "REDACTED-SW01" time timezone 120 module 1 type J9147A module 2 type J9008A module 3 type J9149A no stack trunk B1 Trk3 Trunk trunk B2 Trk4 Trunk trunk A1 Trk11 Trunk trunk A2 Trk12 Trunk vlan 15 name "VM-MGMT" untagged Trk2,Trk5,Trk7 ip helper-address 10.1.10.4 ip address 10.1.11.1 255.255.255.0 tagged 37-40,Trk3-Trk4,Trk11-Trk12 jumbo ip proxy-arp exit

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